Diaphragm pump and system



July 21, 1953 B. F. SCHMIDT DIAPHRAGM PUMP AND SYSTEM 3 Sheets-Sheet 1 Filed March 24, 1949 INVENTOR. Jew/4mm f. Jaw/0r y 1953 B. F. SCHMIDT DIAPHRAGM PUMP AND SYSTEM 3 Sheets-Sheet 2 Filed March 24, 1949 w MM M d .0 m mm M M M July 21, 1953 Filed March 24, 1949 B. F. SCHMIDT DIAPHRAGM PUMP AND SYSTEM 3 Sheets-Sheet 3 INVENTOR. iI/V/lfi/NE jaw/0r Patented July 21 1953 UNITED STATES PATENT OFFICE This invention relates to diaphragm pumps and in general has for its object the provision of a pumping system wherein one or more diaphragm pumps can be operated under the influence of an oscillating fluid column.

Another object of this invention is the provision of a pumping system wherein reciprocation of the diaphragm of a diaphragm pump is effected by a first fluid column in direct communication with said diaphragm and which is oscillated by a second fluid column, said second fluid column being placed alternately in communication with the high and low pressure sides of a working medium pump.

Still another object of this invention is the provision of a pumping system wherein two pairs of diaphragm pumps are operated under the influence of two pairs of first oscillating fluid columns, selectively oscillated by two pairs of second oscillating fluid columns alternately communicating through an automatic valve with the low and high pressure sides of a fluid working medium pump.

The invention possesses other advantageous features, some of which, with the foregoing, will be set forth at length in the following description where that form of the invention which has been selected for illustration in the drawings accompanying and forming a part of the present specification is outlined in full. In said drawings, one form of the invention is shown, but it is to be understood that it is not limited to such form, since the invention as set forth in the claims may be embodied in a plurality of forms.

Referring to the drawings:

Fig. 1 is a top plan view of a hydraulic pumping system embodying the object of my invention, with portions thereof broken away better to illustrate its construction.

Fig. 2 is a section taken on the line 2-2 of Fig. 1.

Fig. 3 is a vertical section taken on the line 33 of Fig. 1 showing the details of the diaphragm pump assembly.

Fig. 4 is a vertical section taken on the line 4-4 of Fig. 1 showing further details of the diaphragm pump assembly.

Fig. 5 is a diagrammatic flow sheet illustrating my pumping system.

figures and as best shown in Fig. 5 comprises a pair of laterally opposed diaphragm pump assemblies generally designated by the letters A and A a pair of laterally opposed piston pump assemblies for hydraulically actuating the diaphragm pumps and generally designated by the letters B and B a pair of automatic valve assemblies generally designated by the letters C and C, operating in synchronism with the piston pumps and a fluid working medium pump assembly generally designated by the letter D and serving as a common means under the control of the valve assemblies, for actuating the pump assemblies B and B The two diaphragm pump assemblies are identical as likewise are the piston pump and automatic valve assemblies, However due to the settings of the movable valve plugs of the valve assemblies, relative to each other, the two piston pumps and the two diaphragm pump assemblies always operate in opposed directions relative to each other. The diaphragms of the diaphragm pumps are actuated hydraulically by liquid columns oscillated by the pistons of the piston pumps and the pistons are driven hydraulically by being selectively subjected through the operation of the automatic valve assemblies, to the low and high pressure sides of a working medium pump included in the working medium pump assembly D.

Diaphragm pump assemblies Each of the diaphragm pump assemblies A and A comprise a pump and valve casting I formed at either end with inwardly dished slurry recesses 2 and 2a. Preferably the surface of each such recess is provided with ribs 3 forming channels for the passage of slurry. Formed on the inner sides of each of the castings I is a slurry intake compartment 4 communicating through a T 5 with a pipe 6 which in turn communicates with a source of the slurry to be pumped. Located above each of the chambers 4 are pockets I and 8 defined in part by a vertical wall 9 and a horizontal wall I I formed as integral parts of the castings I. Mounted in the horizontal wall II within each of the pockets 1 and Bare valve seats I2 and I3 and arranged to seat on these valve seats are poppet valves I4. Each of the poppet valves I4 includes a downwardly extending stem I5 sealed to and slidable within a bearing I6 carried by a spider I'I formed as an integral part of the valve seats I2 and I3. Extending upwardly from the poppet valves I4 concentrically therewith, is a stem I8 sealed to and arranged to telescope within a vented cylindrical guide member I9. The guide members I9 are screwed to and depend from a cover plate 2I bolted to the upper face of the valve casting I.

Operatively disposed between the lower face of the cover plate 2! and the upper face of the poppet valve I4 is a spring 22 serving resiliently to urge the poppet valve to its closed position.

Formed on the outer side of each of the castings I is a slurry outlet chamber 24 communicating with a slurry outlet pipe 25. Disposed below the chamber 24 are pockets 21 and 28 defined in part by the vertical wall 9, the horizontal Wall H and a vertical longitudinally extending mid-Wall 29. Mounted in the horizontal wall I I, within the chambers 24 are slurry outlet poppet valves generally designated by the reference numerals 3i! and 3i, the construction and operation of which are identical to the slurry intake poppet valves previously described.

Bolted over each of the dished recesses 2 and 2a of each of the castings I is an outwardly dished cap 33 and clamped between each of the caps 33 and its associated casting are grids 34 and 35 and a rubber diaphragm 35, the grids 34 and 35 serving to support the diaphragm 35 when the diaphragm is in either of its extended positions.

From this construction it will be seen that each of the outwardly dished caps 33 and its associated dished casting define a chamber elliptical in cross-section and divided by its diaphragm 36 into an inner slurry chamber 37 and an outer working medium chamber 38. Each of the slurry chambers 31 communicates through a port 39 formed in the casting with one of the slurry pockets l or 8 and through the poppet valves associated with these pockets, with one of the slurry chambers 4. Similarly, each of the slurry chambers 37 communicates through a port M with one of the slurry outlet pockets 2? or 28 and through the poppet valves 35 and 3,! associated therewith, with the slurry outlet chamber 24,

Piston pump assemblies The piston pump assemblies are disposed between and somewhat to the left of the two opposed valve castings i as viewed in Fig. 1, and include a pair of symmetrically located double acting piston pumps generally designated by the der heads 54 and 55 and similarly fastened to the opposed ends of each of the cylinders 53 are cylinder heads 56 and 51. Sealed to and extending between the closed cylinder heads 55 and 56 is a sleeve 58 and mounted within this sleeve is a bushing 59. Connected to each of the cylinder heads 54 is a conduit or gooseneck 5| the outer end of which is connected to one of the dished caps 33 and communicates with the Workin medium chamber 38 formed therein. Similarly connected to each of the cylinder heads 5'! is a gooseneck 82 the outer end of which communicates with another of the working medium chambers 38 formed in the outer end of the dish-shaped cap 33. Disposed within each of the cylinders 52 and 53, respectively, are pistons 63 and 64 interconnected by a common piston rod 65 extending through the inner piston heads 55 and 55 and sealed thereto. Fastened to the left end of the piston rod 65 and forming a continuation thereof is a stem 55 extending through and sealed to a boss Bl formed in the gooseneck 6 I.

a standard four way valve includinga cylindrical valve body 68 formed with two pairs of opposed ports 69 and I6 and H and 12. Mounted for rotation or oscillation in the valve body 68 is a valve cylinder or plug 13 provided with two passageways arranged to establish communication selectively between any two adjacent pairs of ports or the valve body. Fastened to the plug 13 is a crank '14, the outer end of the crank being operatively connected to the stem 65 in such fashion that the linear reciprocatory movement of the stem will be translated into rotary movement of the plug 13. In the upper piston pump and valve assemblies B and C these members are so arranged that when the stem 58 is in its right hand limiting position the passageways of valve plug 13 establish communication between the valve ports ll and 10 and between the valve ports 69 and 12. Concurrently the valve plug of the valve assembly C establishes communication between its ports TI and H1 and between its ports 59 and 72. A reversal of the positions of the two stems 56 will of course result in a reversal of the positions of the valve plugs with which they are associated.

Extending between the ports H and the cylinder heads 55 and 56 of each pair of valve and piston pump assemblies is a pipe 16. In the piston pump assembly B the right hand end of the pipe 16 overlies ports H formed in the cylinder head 55 whereas in the opposed assembly B the corresponding pipe 16 communicates with the right end of the lower cylinder 52 through ports li formed in its cylinder head 55. Similarly a pipe "l8 establishes communication between the port 12 of the valve assembly C and the right hand end of its associated cylinder 52 through ports 19 and a pipe l8 establishes communication between the port 12 of the valve assembly C and the left hand end of its associated cylinder 53 through ports 19 Fluid working medium pump assembly The ports T5 of each of the valve bodies 68 communicate through a Y 8| with a working medium supply tank 82 which in turn communicates through a pipe 83 with the low pressure side of a working medium pump 84 of any standard construction. Connected to the high pressure side of the pump 84 is a pipe 85 terminating at its free end in connections 85 and 87 to which additional working medium pumps may be connected as desired. Connected to the pipe 85 intermediate its ends are a pair of pipes 88 communicating respectively with the ports 69 of the two valve bodies 58.

In the operation of the pumping system above described, slurry such as for example rotary mud is delivered through the pipe 6 and through the intake valves of each of the castings l to the slurry chambers 3'! of each of the four diaphragm pumps. Concurrently a fiuid working medium such as oil contained in the tank 82 is pumped by the working medium pump 84 through the pipes 85 and 88 into the ports 69 of the valve bodies 68 and through the passageways in the valve plugs, alternately into the inner ends of the cylinders 52 and 53. While oil is being pumped into the inner end of one of the cylinders 52 and 53 oil contained within the inner end or" the opposed cylinder flows therefrom through one or the other of the pipes l5 and 18*, through the valve body 68 and its plug 13, through the Y 8| into the supply tank 32 and hence to the low pressure side of the pump 84. As a result of the consequent reciprocatory movement of the pistons 63 and 64, the column of oil contained in the goosenecks El and 62 is made to oscillate to thereby operate the diaphragms of each pair of diaphragm pumps. The diaphragms of each pair of pumps always move in the same direction but have opposed cycles so that while one is making its slurry intake stroke the other is discharging slurry. Furthermore as the diaphragms, of one pair of pumps move in one direction the diaphragms of the other pair of pumps move in the opposite direction. By resorting to these sequences of operation a substantially constant flow of slurry through the slurry outlet manifold is obtained and also a substantially constant fiow of working medium through the working medium pump circuit.

A further advantage of this system is that the pump diaphragms are subjeced to hydraulic pressure only during their actual working strokes and are not, after the completion thereof, unduly squeezed against their retaining grids. This results'from the fact that the strokes of the hydraulic columns by which the diaphragms are actuated are predetermined and fixed.

I claim:

1. A pumping system comprising: first and second diaphragm pumps respectively including first and second working medium chambers; first and second axially aligned piston pumps respectively including first and second cylinders and first and second pistons arranged to reciprocate respectively in said first and second cylinders, said pistons being interconnected by a common piston rod; pipes connectingsaid first and second chambers respectively with the outer ends of said first and second cylinders; a closed hydraulic working medium circuit including a working medium pump; pipes leading from the inner ends of said first and second cylinders, a valve connected to said pipes for alternately establishing communication between said closed circuit and the inner ends of said first and second cylinders to deliver working medium under pressure through said last named pipes alternately against the sides of said pistons presented to the inner ends of said cylinders and alternately relieve such pressure from said pistons to reciprocate the pistons and said piston rod; and means for actuating said valve in response to the movement of said piston rod.

2. A pumping system comprising: first and second diaphragm pumps, each divided by its diaphragm into a slurry chamber and a working medium chamber; first and second axially aligned piston pumps, each including a floating piston dividing its cylinder into opposed outer and inner chambers, said pistons being interconnected by a common piston rod; hydraulic lines connecting the Working medium chambers of said diaphragm pumps respectively with the outer chambers of said piston pumps; a hydraulic circuit including a working medium pump and connected at one end to the inner chamber of one of said piston pumps and at its other end to the inner chamber of the other of said pumps; and valve means shunted across said hydraulic circuit and responsive to the movement of said piston rod for alternately reversing the flow of working medium to and from the opposed chambers of said piston pumps.

3. A pumping system comprising: a first unit, having first and second diaphragm pumps, each divided by its diaphragm into a slurry chamber and a working medium chamber; first and second axially alignedpiston pumps, each including a floating piston dividing its cylinder into opposed outer and inner chambers, said pistons being interconnected by a common piston rod; hydraulic lines connecting the working medium chambers of said diaphragm pumps respectively with the outer chambers of said piston pumps, a, hydraulic circuit including a working medium pump and connected at one end to the inner chamber of one of said piston pumps and at its other end to the inner chamber of the other of said pumps; and valve means shunted across said hydraulic circuit and responsive to the movement of said piston rod for alternately reversing the flow of working medium to and from the opposed chambers of said piston pumps; and a second unit identical With the above described unit with exception of having its valves arranged to operate out of phase with respect to the valve means of the first unit, there being a common outlet from the pumps for delivering fluid at a substantially constant rate and pressure from said pumps.

BENJAMIN F. SCHMIDT.

References Cited in the fileof this patent UNITED STATES PATENTS Number Name Date 33,936 Fitzgerald Dec. 17, 1861 482,840 Booth Sept. 20, 1892 728,413 Reynolds May 19, 1903 1,614,100 Carrey Jan. 11, 1927 2,026,479 Logan Dec. 31, 1935 

